The US ambassador to the United Nations, Nikki Haley, has cast doubt on American athletes’ participation in next year’s Winter Olympics in South Korea due to heightened tensions with North Korea.

When asked in an interview on Fox News if US participation was a “done deal,” Haley said: “There’s an open question. I have not heard anything about that, but I do know in the talks that we have – whether it’s Jerusalem or North Korea – it’s about, how do we protect the US citizens in the area?”

Haley said the decision on whether to allow US athletes to travel to South Korea would “depend on what’s going on at the time in the country – we have to watch this closely and it’s changing by the day”.

She added that the US administration would “find a way” to ensure US athletes’ safety if they take part in the games, which open in Pyeongchang on 9 February.

The South Korean town stands just 80 km (50 miles) from the demilitarized zone, the heavily armed border that has divided North and South Korea since their 1950-53 conflict ended in a truce – meaning the countries are still technically at war.

Asked if she thought it was safe to send athletes to South Korea, Haley said: “I think those are conversations we are going to have to have, but what have we always said? We don’t ever fear anything, we live our lives, we use our freedom, we have that.

“And certainly [Pyeongchang] is a perfect opportunity for all of them to go and do something they have worked so hard for. What we will do is, we will make sure that we’re taking every precaution possible to make sure that they’re safe and to know everything that’s going on around them.”

Any suggestion that the US team could miss the Games will cause consternation in South Korea, where preparations have been frustrated by slow ticket sales and concerns among participating countries over the increasingly tense nuclear standoff between North Korea and the US.

In September, France’s sports minister, Laura Flessel, said the country’s athletes would not take part if the nuclear crisis deepened and athletes’ security could not be guaranteed. French athletes, however, have said they are optimistic about competing.

Pyeongchang organisers are also reeling from the International Olympic Committee’s decision to ban Russia from the Pyeongchang Games over its state-sponsored doping programme.

South Korea’s government recently attempted to reassure other countries, including the US, that the Pyeongchang games would be “the safest in Olympic history”.

It has reportedly taken extra security measures, including the formation of a unit to counter cyber attacks and a doubling of the number of troops.

South Korean officials pointed out that the country has a track record of organising trouble-free international sports events, including the 1988 Seoul Olympics and the 2002 World Cup, which it co-hosted with Japan.

Any prospect that political tensions would be eased by the presence of North Korean athletes ended last week when the figure skating pair Ryom Tae-ok and Kim Ju-sik – the only North Koreans to have qualified for the Olympics – missed the deadline to register for their event.